Carburetor



JQ. l.. G. Lum-WHT CARBURETOR Filed NOV. 4, 1939 2 Sheets-Sheet l :NVENTOR ATTORNEYS Patented Jan. 14, 1941 UNITED STATES PATENT OFFICE 2 Claims.

This invention relates to carburetors and has for an object to provide an improved construction wherein the gasoline or other liquid fuel is mixed with air, or carbureted in a preliminary sense, and then passed through a second carbureting structure before it is discharged into the intake manifold of an internal combustion engine or other device using carbureted fuel.

Another object of the invention is to provide a carburetor provided with a plurality of jets, one of which acts as an idling jet for an engine, the jets being associated with means for exposing one or more jets at a time according to the power desired.

In `the accompanying drawings- Fig. 1 is a longitudinal vertical sectional View through a carburetor embodying the invention;

Fig. 2 is a sectional view through Fig. l approximately on the line 2--2;

Fig. 3 is a plan View of a shutter embodying certain features of the invention;

Fig. 4 is a fragmentary sectional view through Fig. 1 approximately on Ithe line 4 4;

Fig. 5 is a View similar to Fig. 4 but showing the shutter in an advanced position;

Fig. 6 is a view similar to Fig. 5 but showing the shutter in its fully advanced position; and

Fig. 7 is a fragmentary sectional view through Fig. 1 on the line 'I-'I.

Referring to the accompanying drawings by numerals, I indicates a housing provided with a float chamber 2 and a nozzle chamber 3. The housing is also provided with a plurality of liquid fuel passageways 4, 5 and 6 extending from the float chamber 2 to spaced points in the housing 3. As illustrated particularly in Fig. 1, the housing is thickened at the places where the passageways are located. At the end of eachpassageway there is provided a nozzle, the nozzle 8 being in free communication with passageway 5, while nozzles 9 and I3 are in free communication with the passageways 4 and 5. A hand-actuated needle valve il is provided with each nozzle for varying the outlet opening thereof. The housing I is also provided with an air inlet opening I2, whereby ample air is provided for the housing, said air being drawn into the carburetor through the suction of the internal combustion engine to which the carburetor is connected. The top I3 of the housing I is flat and is provided with three outlets, namely, outlets I4, I5 and IIi. Each of these outlets is provided with an air tube I1, as shown in Fig. 1. This tube is appreciably larger than the nozzle so that whenever the engine produces suction the air in the housing I (C1. tliswill pass upwardly as indicated by the arrows I8 and Will draw some of the liquid fuel from nozzle and discharge the same into the mixing charnber or primary or carbureting chamber I9. This chamber is mounted on the top I3 and is held in place in any suitable way, as for instance, by means of screws 20. The chamber I9 is formed from part of the top I3 and a housing 2I, which housing has a thickened portion 22 provided with a passageway 22. A gasoline or other liquid fuel pipe 24 supplies liquid fuel-to a passageway 23 and the fuel passes from thence into the chamber 2 when the valve 25 on a float 2B is moved away from valve seat 21.

A shutter 28 formed preferably fiat rests on the at top I3 and acts to vary the openings or outlets I4, I5 and I6 according to the amount of fuel desired. Shutter 28 is shown in top plan in Fig. 3. From this figure it will be observed there is provided a shutter outlet or opening 29 of the saine size as the outlet I6 and a second outlet 33 which is elongated circumferentially until it is slightly more than twice as long as the diameter of the opening. These openings are so proportioned and arranged that when the elongated opening 3U is about to leave outlet i4, as shown in` Fig. 4, it exposes some of outlet I5 so that as the amount of fuel passing from outlet I4 decreases the amount of fuel from outlet I5 increases. A rock shaft 3I is rigidly secur-ed to the shutter 28 and as it is rocked or rotated in one direction or the other the shutter moves. As the shutter moves to the right, as illustrated in Figs. 4 and 5, the opening I4 will become covered and opening I5 will become comi pletely uncovered. If the shutter moves to its extreme position the parts will be as shown in Fig. 6 with both the openings I5 and I Ii exposed.

Shaft 3| has an arm 32 rigidly secured thereto, as shown in Fig. 1. A spring33 acts against arm 32 and the bottom of housing I to maintain a frictional contact between the shutter 28 and the top of housing I3. A rod 34 is pivotally connected at 35 to the outer end of arm 32 and at 36 to the lever 31 which is rigidly secured to shaft 38. The usual buttery valve 39 is arranged in the tube 40 and is rigidly secured to shaft 38. A control rod 4I is connected to lever 3l for swinging the same back and forth. Usually in automobiles, a spring is used to move rod 4I so as to close the valve 36 or move the same to the position shown in Fig. 1.

The accelerator ypedal is depressed by the operator and when depressed the rod 4I will move as indicated by the arrow 42 for opening valve 39 and, at the same time, rotating the shutter 28 so as to expose opening I5 or openings I5 and I6, as desired. When the accelerator pedal is released, the spring will move the parts back to the position shown in Fig. 1 and the opening I4 will be fully exposed through the elongated opening 30 and the other two openings, namely, openings I5 and I6 will be closed. This will allow the engine to idle.

As the engine functions, rarefaction or suction will be produced and this will draw air from the housing I and with the air a certain amount of gasoline or other liquid fuel which is somewhat mixed Iin the `various tubes I1 and further mixed in the mixing chamber I9. As this mixture of air and fuel moves into the inlet chamber 43, it will be additionally mixed or carbureted, and as this mixture moves through the tubular member 44, which with its associated parts forms a c-arbureting chamber, it will .be fully carbureted .and discharged into the outlet chamber 45 as carbureted fuel. The carbureted fuel passes into the pipe 40 and thence into the intake manifold of the engine.

The parts just described are preferably made of metal and interiorly of the metal tubular member 44 Iare a number of rings 45, there being ve shown in the accompanying drawings. These rings are spaced apart and each ring is provided with a plurality of equally spaced blades or baffles 41 extending radially inwardly for approximately half the distance between the inner surface of the tubular member 44 and the center of the power shaft 48. The power shaft 43 extends entirely through the tubular member 44 and also preferably through the chambers 43 and 45. A pulley 49 is rigidly secured to the shaft 48 and is driven by Ia belt 5i), which in turn is driven by some movable part of the engine. On the shaft 48 a number of beating and mixing members 5I are mounted, said members being secured in place by pins or other desi-red means so that they will rotate with the shaft 43. Each member 5I is provided with a radiating flange 52 which extends radially outwardly to near the inner ends of the bailies 4l'. The stirring and mixing blades 53 are also formed integral with the flanges 52 and the heads 54. The blades or spokes 53 are arranged between adjacent baiiles 41 so tha-t when these blades rotate, preferably at a rather high rate of speed, the mixture passing through the tubular member 44 will be thoroughly carbureted before i-t reaches the outlet chamber 45.

Each of the rings 46 is preferably provided with a plurality of projections 46 so that these rings will be equally spaced apart. These rings may be held in place by screws or, if desired, by friction.

In oper-ation, when the parts are positioned as shown in Fig. 1 and the engine to which the car- -buretor is attached is functioning, shaft 48 will be rotating rather slowly and liquid fuel will be discharged from nozzle 8 which is the idling nozzle. This fuel will be carbureted and discharged eventually into the intake manifold and then distributed to the cylinders in the usual way. When it is desired to operate the engine at a higher speed, the rod 5I is moved as indicated by the arrow 42 and the butterfly valve 39 will open to allow a fuller action of the suction from the engine. At the same time, the shutter 28 will move, for instan-ce from the yposition shown in Fig. 1 to that shown in Fig. 4 and then to the position shown in Fig. 5. If more power is needed, the rod 4I is moved further in the direction of the arrow 42 and the shutter 28 will be fully opened as shown in Fig. 6, whereupon the maximum amount of fuel is discharged into the mixing chamber I9 Iand is passed through the carbureting chamber formed by the tubular member 44 and associated parts. By this construction it will be seen that -there is a double carburetion, namely, a preliminary carburetion in chambers I9 and 43 and a more :complete ca-nburetion in the tubular member 44.

I claim:

1. A carburetor including a tubular casing open at both ends, substantially L-shaped hollow member connected to each end of said tubular casing, a plurality of spaced rings positioned in said casing between the ends thereof with their oulter surface in Contact with the inner surface of the casing, each of said rings having spaced inwardly extending vblades falling appreciably short of the longitudinal center of said casing, a rotating power shaft extending longitudinally through the center of said casing and a plurality of stirring and mixing members rigidly secured to said shaft, each of said mixing members being provided with a hub, a radially extending ange on each hub and a plurality of radially extending blades projecting beyond said flanges to near the inner surfaces of said rings the blades being positioned within and between certain of said rings.

2. A carburetor including a tubular casing open at both ends', a plurality of spaced rings positioned in said casing between the ends thereof with their outer surf-aces in contact with the inner surface of the casing, each of said rings having spaced inwardly extending blades falling appreciably short of the longitudinal center of said casing and spacing projections for spacing said rings, said spacing .projections extending parallel to the casing and from one ring to the other and a rotatable stirring and mixing structure including a lplurality of `contacting hubs arranged centrally of said tubular casing, each hub having centrally thereof .a radiating flange and a blade extending laterally of the iiange and also radially thereof, the blades of the stirring and mixing structure passing in between said rings and a shaft extending through and connected with all of said hubs for causing the hubs to move in unison.

GUNVALD G. LINDTVEIT. 

